1. Field of the Invention
The present invention relates to a wrench for imparting a torque on an object, and more particularly, but not by way of limitation, to a wrench apparatus for selectively rotating and removing a control plate located in a skimmer of a swimming pool filter system.
2. Description of Prior Art
Swimming pools are typically constructed with a filter system to remove dirt and debris from the pool water. The filter system is provided with a pump which withdraws water from the pool through an inlet port, passes the water through a filter, and injects the filtered water back into the pool via outlet ports positioned on the sides of the pool. The inlet port of the filter system is commonly located in the bottom of a skimmer, a reservoir placed adjacent to the pool to collect larger debris floating on the surface of the water, such as bugs and leaves.
Several designs for skimmers exist in the swimming pool industry. That is, the design of a skimmer may vary in the accessories and the positioning of such accessories in the skimmer, as well as in the design of the plumbing for the skimmer However, a common skimmer design for swimming pools has an inlet port for the filter system located on the bottom of the skimmer and a port positioned on the side of the skimmer which is connected to the main drain so that water is circulated from the drain to the filter system via the skimmer. A filter basket is inserted in the bottom portion of the skimmer to collect the larger debris floating on the surface of the water. In addition, a control plate is secured in the skimmer above the filter basket to control the rate of water flowing through the upper portion of the skimmer and to provide a convenient way to connect a vacuum device to the filter system in order to clean the bottom of the pool.
The control plate is a substantially funnel-shaped member having a central opening. The rate water flows through the central opening of the control plate is dependent on the rotational positioning of the control plate. By engaging upwardly extending ear members on the control plate, the control plate can be selectively rotated between a normal operating position, a vacuuming position and a removal position.
In the normal operating position, the filter basket collects debris from the water flowing through the central opening of the control plate, as well as debris in the water flowing into the skimmer from the main drain. In the vacuuming position, the control plate is rotated so that the port from the main drain is blocked. Thus, the flow rate of water through the central opening of the control plate is increased which enhances the suction available to a vacuum device connected to the control plate. On the other hand, when the control plate is rotated to the removal position, the control plate can be removed from the skimmer so that the filter basket can be emptied.
The control plate is rotatably secured in the skimmer by inserting male members of the control plate into a female member of the skimmer, typically a groove formed in the side of the skimmer. This groove often becomes filled with dirt and debris which, in combination with a rubber seal located about the peripheral edge of the control plate, makes rotation of the control plate difficult. Consequently, conventional wrenches are often used to rotate the control plate. However, use of tools such as conventional wrenches may result in the breaking-off of the ear members from the control plate. In addition to problems in rotating the control plate, difficulties also arise in removing the control plate from the skimmer as a result of the awkward placement of the control plate in the skimmer.
Thus, a need has long existed for a wrench apparatus which enables a control plate located in a skimmer to be easily rotated to a desired operational position and, at the same time, provides a convenient way to remove the control plate from the skimmer. It is to such a wrench apparatus that the present invention is directed.